Early in the morning on July 16, 1945, the first atomic
bomb blast was detonated at the Trinity Site. The actual explosion produced a
blast equivalent to eighteen thousand tons of TNT. The resulting fireball that
scorched the desert formed a depressed crater 800 yards in diameter, glazed with
a light olive green, glass-like substance where the sand had melted and
solidified again. The following excerpt is from Time Magazine, Sept. 17, 1945:
“Seen from the air, the crater itself seems (looks like) a lake of green Jade
shaped like a splashy star, and set in a sere disc of burnt vegetation half a
mile wide. From close up the lake is a glistening encrustation of blue-green
glass 2,400 feet in diameter, formed when the molten soil solidified in air.”
Chemical tests have confirmed that it is nearly pure melted silica with traces
of Olivine, Feldspar, and other minerals which comprise the desert sand. The
crater was buried for security reasons not long after the explosion and, as a
result, Trinitite has remained relatively difficult to obtain. This material
was, of course, collected many years ago. A copy of a one page report, taken
from “Minerals of New Mexico”, S. A. Northrop (1959) is available covering
Trinitite, and a copy of this information will be supplied with each sample
ordered, if requested. Each specimen has the light olive green,
glass-like, fused top surface, with interesting rounded form. The bottom of each
piece exhibits the rough texture of the sandy desert surface, which remained
untouched by the blast. While the Trinitite was highly radioactive in 1945 when
it was formed, more than fifty years have passed and at the present time, the
radioactivity is very low.

AERIAL VIEW OF GROUND
ZERO

The crater and heat scars (light green) on the desert at ground zero.
Trinitite glazed much of the dark green area seen in the center of this illustration.

EARLY MORNING -
JULY 16, 1945

A fireball more than 500 meters in diameter rose to a height of 40,000 feet,
and illuminated the southern New Mexico sky.